Haematological Tests Flashcards
What is measured in iron studies?
- Serum Iron
- Total Iron binding capcity
- Serum Ferritin
What are the following?
Acanthocytes - spicules on RBCs, due to RBC membrane lipid structure
What are causes of acanthocytes?
- Splenectomy
- Alcoholic liver disease
- Spherocytosis
- Haemoglobinopathy
What can cause blast cells in plasma?
- Myelofibrosis
- Leukaemia
- Malignant bone marrow infiltration
What is the following?
Basophilic stippling - denatured RNA found in RBCs, indicating accelerated erythropeises of defective Hb synthesis
What can cause Basophilic stippling?
- Lead poisoning
- Megaloblastic anaemia
- Leukaemia
- Malignant infiltration
What are the following?
Cabot rings - thin, red-violet staining, threadlike strands in the shape of a loop or figure-8 that are found on rare occasions in red blood cells (erythrocytes)
What are causes of cabot rings?
- Pernicious anaemia
- Lead poisoning
- Bad infections
What is the following?
Howell jolly bodies - DNA nuclear remanats in RBCs, which are normally removed by the spleen
What are causes of Howell-Jolly Bodies?
- Post-splenectomy
- Hyposplenism
- Myelodysplasia
- Megaloblastic anaemia
What is the following?
Hypochromia - less dense staining of RBCs caused by decreased Hb synthesis
What is the following?
Poikilocytosis - variation in RBC shape
What are causes of poikilocytosis?
- IDA
- Myelofibrosis
- Thalassemia
What are the following?
Reticulocytes - Young, large RBCs signifying active erythropoeisis
When might you see reticulocytosis on blood film?
- Haemolysis
- Haemorrhage
- If B12, folate or iron given to marrow that lack these nutrients
What are the following?
Spherocytes - spherical cells found in hereditary spherocytosis and autoimmune haemolytic anaemia
What are the following?
Rouleaux formation - red cells stacked on each other, causing a rasied ESR
What can cause rouleaux formation?
- Chronic inflammation
- Paraproteinaemia
- Myeloma
What are the following?
Schistocytes - Fragmented RBCs sliced by fibrin bands, in intravascular haemolysis
What are causes of schistocytes?
Microangiopathic anaemia
- DIC
- Haemolytic uraemic syndrome
- TTP
- Pre-eclampsia
What causes increased neutrophil count (neutrophilia)?
- Bacterial infections
- Inflammation
- Myeloproliferative disorders
- Drugs
- Disseminated malignancy
- Stress - trauma, surgery, burns
What are causes of decreased neutrophil count (neutropenia)?
- Viral infections
- Drugs - post chemo, cytotoxic agents, carbimazole
- Severe sepsis
- Neutrophil antibodies - SLE
- Hypersplenism - felty’s syndrome
- Bone marrow failure
What causes increased lymphocyte count?
Lymphocytosis
- Acute viral infection
- Chronic infections - TB, brucella, syphilis
- Leukaemias - esp. CLL
- Lymphomas
When might you see a decreased lymphocyte count?
- Steroid therapy
- SLE
- Uraemia
- Legionnaire’s Disease
- HIV infection
- Marrow infiltration
- Post-chemo/radiotherapy
What could cause eosinophilia?
- Drug reaction
- Allergies - asthma, atopy
- Parasitic infection
- Skin disease
- Malignant disease
- Adrenal insufficiency
- Irradiation
What causes Monocytosis?
- Post chemo/radiotherapy
- Chronic infections
- Malignant disease
- Myelodisplasia
What is the prothrombin time?
Along with its derived measures of prothrombin ratio (PR) and international normalized ratio (INR)— PT assays evaluate the extrinsic pathway of coagulation. They are used to determine the clotting tendency of blood, in the measure of warfarin dosage, liver damage, and vitamin K status
Which clotting pathway does the PT look at?
Extrinsic Pathway
Which pathway does the APTT look at?
Intrinsic pathway
What is the APTT?
Activated partial thromboplastin time (aPTT or APTT)
Partial thromboplastin time (PTT) measures the overall speed at which blood clots by means of two consecutive series of biochemical reactions known as the “intrinsic” (now referred to as the contact activation pathway) and common coagulation pathways.
What is ESR a measure of?
Time taken for blood to sediment at bottom of tube if left to stand - heavier the blood, the quicker the sedimentation rate
Why might ESR increase?
Inflammatory/Autoimmune conditions which increase fibrinogen or IgG production - causes red cells to clump together
